Generally in case a vehicle as the moving object passes through a toll road, there is made the so-called “accounting process”, in which the vehicle is charged with a toll according to its type or covered distance. In this accounting processing case, facilities such as gates or tollbooths were conventionally provided at the entrances and exits of the toll road. If the method of providing such facilities is adopted, however, there arise problems that the works to dispose or transfer the facilities themselves are troublesome, and that the landscapes and spectacles around the road are deteriorated by the facilities. Thus, there has been known a device, which can make the aforementioned accounting process without disposing the aforementioned facilities on the road. One example of the device is described in Japanese Patent Laid-Open No. 2000-123213.
This accounting processor described in the Laid-Open is provided with a on-vehicle unit mounted on a vehicle, and an external information unit disposed outside of the vehicle. The on-vehicle unit constructs a portion of the so-called “navigation system” and is provided with an electronic control unit. Moreover, this electronic control unit is constructed of a microcomputer, which is composed mainly of a processor, a storage unit and an input/output interface. With the electronic control unit, there are connected a map database, an input unit, a GPS (i.e., the capitals of Global Positioning System) antenna, and a ground communication unit. This map database is stored with the information on the roads of the map, the information on the accounting zones in the roads and so on. On the other hand, the display unit is provided for operations to input the present position and the destination of the vehicle, or the travel route of the vehicle. Moreover, the display unit indicates the present position of the vehicle in the map data. Moreover, the GPS antenna is provided for receiving signals transmitted from artificial satellites. Still moreover, the ground communication unit is provided for communicating with an integrated center placed on the ground.
The external information unit is constructed to include the artificial satellites and the integrated center. This integrated center is provided with a ground communication unit for communicating with the ground communication unit of the on-vehicle unit, a map database stored with map data determining the accounted zones and the tolls, and an electronic control unit connected with the ground communication unit and the map database.
In the accounting processor described in the aforementioned Laid-Open, the position of the vehicle in the map data is detected by receiving the signals transmitted from the artificial satellites through the GPS antenna of the on-vehicle unit and by processing the received signals. On the basis of the detection result of the position of the vehicle, moreover, it is decided whether the vehicle is positioned in the accounting zone or in the unaccounting zone. Moreover, the position information of the vehicle is transmitted through the ground communication unit of the on-vehicle device to the integrated center. On the basis of the received position of the vehicle, the integrated center makes an accounting process based on the accounting zone and transmits the process result to the on-vehicle unit.
Here in the detection of the position of the vehicle by the artificial satellites and the GPS antenna, a detection error is inevitably caused by the arrayed state of the artificial satellites. Thus, there arises a problem that an erroneous accounting is generated by collating the detection result containing an error and the accounted zone of the map data. In the accounting processor described in the Laid-Open, therefore, a buffer zone is set between an accounted zone and an unaccounted zone of the map data. This buffer zone is set on the basis of a distance corresponding to the detection error of the position of the vehicle. Moreover, the accounting processor is constructed such that the decision that “the vehicle exists in the accounting zone” is not made in case it is decided that the position of the vehicle is in the buffer zone. By thus setting the buffer zone, an erroneous decision on which of the accounting zone or the unaccounting zone the vehicle takes a position is prevented from being made on the basis of the position detecting precision of the vehicle.
In the accounting device described in the aforementioned Laid-Open, however, the error of the position detection of the vehicle is coped with setting the buffer zone between the accounting zone and the unaccounting zone. Therefore, the quantity of data necessary for the accounting process increases, and the operations necessary for the accounting process are complicated. As a result, problems are that the cost for the accounting device rises, and that the time period for processing the data necessary for the accounting becomes long.
A main object of the invention is to provide a position recognition device, a position recognition method, and an accounting processor and an accounting processing method, which can decide it highly precisely whether or not a moving object has moved from a predetermined zone to another, which can suppress the rise in the manufacture cost, and which can prevent the time period necessary for the data processing from becoming long.